1. Field of the Invention
The present invention relates to a liquid crystal display device, and more particularly to a reflection type liquid crystal display device that can also function as a transmission type device.
2. Description of Related Art
A liquid crystal display device (LCD) is widely used as a planar display device for a variety of portable computers and portable televisions.
Liquid crystal display devices are classified into two types according to their use of a light source. One type is a transmission type liquid crystal display device, which uses a backlight provided on the back face of a liquid crystal panel as a light source. The other type is a reflection type liquid crystal display device, which uses an external light source such as sunlight or an indoor lamp.
It is difficult to decrease the volume, weight and power consumption of a transmission type LCD because of the presence of the backlight which is used as a light source. For a reflection type liquid crystal display device, the volume, weight and power consumption are low, because the reflection device need not use the backlight. However, if an external environment is dark, the reflection type liquid crystal display device cannot be used.